1. Field of the Invention hauling by truck, of cargo of bulk or comminuted and palletized types.
2. Description of the Prior Art
Dump trucks or dumping trailers for hauling comminuted bulk cargo such as sand or aggregate are well known in the art. Similarly, non-dumping trucks and trailers into which palletized units of cargo may be loaded at one point and unloaded at a destination are known Since each type of vehicle has a specialized body, in situations in which a truck hauls cargo of one type to a destination having cargo to be hauled of the other type, the practice has been to return with the empty vehicle back to the loading point. Such dead-head or non-load transporting use has represented a substantial loss of the potential load carrying capacity of vehicles costing approximately $100,000, or more, in addition to the lost time of the operator.
In particular, vehicles for carrying comminuted or palletized cargo have been adapted to carry the load available at only one loading point, thus transporting in only one direction, and thereby losing potential economic value.
The U.S. Pat. Nos. to Sentle 4,221,427 and Clarke 4,557,400 disclose trailer bodies for hauling bulk comminuted material having a cargo area below the level of the floor, and for changing the construction of the floor in order that containerized cargo may be hauled in the other direction.
The U.S. Pat. Nos. to Gibson et al. 2,216,972, DeWitt 2,819,810, Mahoney 3,950,023, Sano et al. 4,009,792, Melley et al. 4,127,300, Weston 4,231,695 and Marshall 4,642,007 disclose trucks having bodies that are particularly designed to facilitate the loading, unloading and hauling of containerized cargo such as pallets, including the use of rails within the vehicle on which wheels on the pallets may ride. The DeWitt patent in particular discloses a system such as that described in which a conveyer chain is employed to assist in the movement of the pallets on the rails.
The U.S. Pat. Nos. to Thornton 1,451,127 and Weber 1,557,749 disclose trucks having bodies that may be placed in the dumping position and which carry dumping type containers.
The U.S. Pat. Nos. to Filipoff et al. 2,789,715, Phillips et al. 3,659,899 and Kreutzer 3,712,491, disclose vehicles in which the load carrying body may be elevated to dumping position, thus permitting transport of dumpable material or other cargo.